Weapon launching rockets and method to use the same

ABSTRACT

A weapon including in combination, a rocket launcher and a gun attached to said launcher with its axis parallel to that of the launcher to move with said rocket launcher, an artillery tracer projectile for firing from said gun constructed to be crushed upon impact with a target to deposit tracer material thereon which continues to burn, and a rocket provided with guidance means for following said tracer projectile through the entirety of its path to impact the position of said deposited tracer material, wherein said guidance means comprises means rotating the rocket about its axis through its trajectory and at least two guidance devices each including a pair of aerodynamic flaps externally and symmetrically arranged on the rocket about an axial plane and independently movable, a lens positioned on said rocket with its optical axis parallel to the axis of the rocket to receive radiant energy from said tracer material as the rocket is launched to follow the path of said projectile, two radiant energy detector cells each symmetrically placed upon two equal sectors of one circle located in the focal plane of said lens with planes identical to that of the corresponding said aerodynamic flaps, insulating sectors smaller than said detector cells spaced between the cells on said circle, amplifiers coupled to the two cells, and control means responsive to the amplifiers for moving said corresponding flaps proportional to the currents generated in the respective detector cells.

United States Patent [191 Joneaux 1 Sept. 17, 1974 WEAPON LAUNCHING ROCKETS AND METHOD TO USE THE SAME [76] Inventor: Pierre Andr Joneaux, Avenue Pinel 6, Asnieres, France [22] Filed: Oct. 25, 1963 [21] Appl. No.: 319,074

[30] Foreign Application Priority Data Oct. 26, 1962 France 913553 [52] US. Cl. 89/l.8, 244/3.16 [51] Int. Cl F41f 3/04 [58] Field of Search 244/14; 102/70.2, 50; 250/203 [56] References Cited 7 UNITED STATES PATENTS 2,403,387 7/1946 McLennan 244/l4.3 2,752,850 7/1956 Warner et a1 102/50 2,942,118 6/1960 Gedance 244/l4.3 3,010,677 11/1961 Guthrie et al l 244/14 3,021,096 2/1962 DeMott 244/14 3,053,984 9/1962 Hulett 244/14 3,097,564 7/1963 Stevenson 89/1.7 A 3,116,039 12/1963 Goldberg 244/14 Primary Examiner-Samuel W. Engle Attorney, Agent, or FirmWatson, Cole, Grindle & Watson [5 7] ABSTRACT A weapon including in combination, a rocket launcher and a gun attached to said launcher with its axis parallel to that of the launcher to move with said rocket launcher, an artillery tracer projectile for firing from said gun constructed to be crushed upon impact with a target to deposit tracer material thereon which continues to burn, and a rocket provided with guidance means for following said tracer projectile through the entirety of its path to impact the position of said deposited tracer material, wherein said guidance means comprises means rotating the rocket about its axis through its trajectory and at least two guidance devices each including a pair of aerodynamic flaps externally and symmetrically arranged on the rocket about an axial plane and independently movable, a lens positioned on said rocket with its optical axis parallel to the axis of the rocket to receive radiant energy from said tracer material as the rocket is launched to follow the path of said projectile, two radiant energy detector cells each symmetrically placed upon two equal sectors of one circle located in the focal plane of said lens with planes identical to that of the corresponding said aerodynamic flaps, insulating sectors smaller than said detector cells spaced between the cells on said circle, amplifiers coupled to the two cells, and control means responsive to the amplifiers for moving said corresponding flaps proportional to the currents generated in the respective detector cells.

1 Claim, 6 Drawing Figures WEAPON LAUNCHING ROCKETS AND METHOD TO USE THE SAME The invention relates to a weapon launching a selfpropelled projectile which is guided by a more precise projectile fired through an auxiliary gun. The invention also relates to the combination of the weapon with the said projectiles and to methods for using the same.

Rockets and some other self-propelled projectiles are not usually guided. With respect to the gun fired projectiles, hereafter called artillery projectiles even if they concern small size bullets, they have the great advantage not to require heavy launching equipment, but they also have the great disadvantage to be much less accurate than self-propelled projectiles. This defect greatly limits the use of rockets.

The invention will be principally described with reference to guidance of rockets but it is applicable, sometimes with different modifications, to missiles of any kind, at least within a part of their trajectories.

The invention consists of firing, at the same time as a self-propelled projectile or at a determined interlapse, an artillery projectile, termed a pilot projectile, which preferably precedes the self-propelled projectile and issues a signal, luminous for instance, towards which a guidance system, borne by the self-propelled projectile, leads the latter.

The principal object of my invention is to give the rockets a firing accuracy approaching that of artillery projectiles or bullets, that is to say, exactly, a firing accuracy near that of the pilot projectile fired through an auxiliary gun.

Other objects of the invention are: to make easier training of the crews, simply requiring normal firing of a rifle or other small weapon; to use the auxiliary or associated arm (rifle or machinegun) as a secondary armament; to use the associated arm for the fire adjustment at the target, before the rocket launching; to allow the crew immediately to break away from the battery position, or to immediately launch one or several other rockets, which is not possible with rockets guided on to target by a pointer.

Other objects and advantages will appear in the following specification.

In order that the invention may be more clearly understood and readily carried into effect, a particular examplification of the invention is drawn on the accompanying drawings, in which:

FIG. 1 is a schematic view in elevation of the weapon, the rocket and the bullet in flight and the target.

FIG. 2 is a schematic view in elevation of the rocket.

FIG. 3 is a diagrammatical drawing of one form of a guidance system for the rocket.

FIG. 4 is a front view of a group of photoelectric cells being a part of the rocket guidance system.

FIG. 5 is a curve of the voltage issued from one of the photoelectric cells.

FIG. 6 shows a device for the rotation of a rocket guidance flap.

The weapon according to the invention consists of a rocket launcher 1 and a gun 2 fastened with the launcher l. The rocket is generally referenced as 3. The pilot projectile is a tracer bullet or a bullet with a rear pyrotechnic flare, fired through the gun 2, visible from the departure out of the gun. The trajectories of the rocket and the tracer bullet are respectively referenced 6 and 7. 'The target is referenced 5.

The features of the rocket and the pilot projectile are selected, according to the known teaching of ballistics, in order that both projectiles, simultaneously fired or with a determined time stagger, have neighbouring flights, the tracer bullet being before the rocket, at least in the useful range limits of the weapon.

The rocket is provided with a known system guiding it from the light of the tracer bullet, as conventional for guidance of missiles towards the light or the heat issued by plane motors. It may also be provided with the guidance system described below, as an example.

The rocket comprises from rear to fore parts: a tail fin 8, a powder propellant 9, a fore body 10 bearing a bursting charge, for example a shaped charge 11, and a known booster device not drawn on the figures (striker, primer, booster).

In the examplification herein described for the guidance, a rocket is selected with low rotation around its axis (a few rotations per second). Preferably, rotation is given from thestart of the rocket by known means, either by means of the launching tube, or by means of the rocket tuyeres. The rotation is maintained by the tailfin.

The guidance system is located in the head 12, and arranged so as practically not disturb the acting of the bursting charge. In the particular case described, the neighbouring of the axis is not obstructed before the bursting hollow charge.

The rocket guidance system includes the following parts: aerodynamic flaps or movable vanes, a detector or sensor unit, a flaps control, an electric battery and amplifiers for electric currents issued from the sensor unit.

There are four flaps 13 -13 they are symetrically arranged near the fore part of the head. Each of them is rotatable around an axis perpendicular with the external surface of the head. The axes of each of two symetrical flaps are joined, by means of universal joints for instance, so as to jointly rotate, as if they have one axis 14 or 15 as in simplified form they are shown on the diagrammatical FIG. 3. One may really couple the flaps in this manner, if desired, by leaving necessary clearance between the flaps and the surface of the head, because of the light rotation amplitude of the The sensor unit consists of a lens 16, the optical axis of which is parallel to the axis of the rocket. The lens glass is preferably selected to let pass the light issued from the bullet tracer and to eliminate the most part of the radiation of the background on which the tracer is to be discriminated. The sensor unit consists also of a group of four photoelectric cells 17, 17, 17", 17 symetrically arranged on one circular disc. The cells are covered with angular sectors 18, opacous to the tracer light, between which are shown active sectors 19. The whole cells are placed in the focus plane of the lens 16 with their center on the optical axis.

Within the possible angular deviation in the location of the tracer bullet in respect of the rocket, the maximum of deviation being only some degrees, the optical image of the bullet is located on the cells disc. Since the rocket rotates around its axis, the optical image of the tracer moves on spiral curves, crossing the active sectors 19 of the four photoelectric cells. Thus, the cells give out a current the voltage U of which has a curve in function of time with rectangular shape (FIG. The lower value of voltage corresponds to the light of the background on which appears the tracer bullet. Since this light is preferably filtered in greater part by the glass of the lens, the minimal voltage is not very high. The rectangular supplement of voltage is due to the tracer light.

The flaps control is diagrammatically shown on FIG. 3. Both flaps 13 and 13 jointly rotate around the same axis 14, rigid with a lever 20. The end of the lever can be magnetised and attracted by one or the other of two electromagnets 21" or 21".

Practically, the lever actuates with a more improved device, such as that of FIG. 6. When not magnetised at its end, the lever 20 is held in a medium position as shown on FIG. 6, in equilibrium between two springs 24 and 26, settled at one of their ends to a frame rigid with the rocket. The other ends respectively bear the plates and 27 which lean against the thrust 29. The end of the lever 20 is fixed in a medium position in consequence of the simultaneous thrust of the two plates 25 and 27. The two electromagnets 21 and 21" attract the magnetic part of the lever 20.

The two other flaps 13 and 13 are respectively provided with the same control means as 13 and 13 The electromagnets 21 and 21" respectively receive the currents issued from the photoelectric cells 17 and 17" when respectively amplified by amplifiers 22" and 22". Necessary power is provided by the battery or other convenient electric source 23.

All the used electric devices may be ordinary staple articles.

Actuation is accomplished in the following manner: The tracer image excites the active sectors of the cells which issue by turns a rectangular current. The current from the cell 17 is amplified by the amplifier 22" and sent on the electromagnet 21 which attracts the lever 20 and rotates the flaps 13 and 13 in a fixed angle, in a determined direction. The direction is selected in such a way that the flaps l3 and 13 incline the head of the rocket towards the tracer direction in come quence of the relative air flow.

The two other flaps l3 and 13 are similarly controled by the photoelectric cells 17 and 17".

The whole flaps, when the tracer image goes through the corresponding photoelectric cells, give the rocket a plurality of short impulses bringing the rocket axis towards the tracer bullet. Thus the rocket is induced to follow the bullet, being drawn nearer the trajectory of the latter, and the rocket hit the target close to the bullet impact.

In order to get the best accuracy, it is interesting that the guidance system may actuate from the time of the rocket launching, during the combustion of the propelling charge, that is when the rocket has the most irregular movements. When the bullet crushes on the target it is also interesting, that the tracer keeps its activity upon the impact till the rocket reaches the target. On the contrary, after the bullet has eventually ricocheted on the target, it is interesting that the tracer has no longer an activity which causes the rocket to deviate its flight.

Two means, for instance, may permit those results: making the bullet with relatively soft material (lead for instance) which crushes on the target, or making the bullet with a weak material, partially at least (glass for instance), so allowing the bullet to be broken on the target. In any case, the remaining of the tracer keeps stuck on the target, when finishing to burn.

The methods for using the weapon so described may be various.

Generally, it is convenient that: on the used part of the theoretical trajectories if the pilot projectile and the missile, that of the latter are considered without the acting of the guidance system, the trajectories are nearest as possible; the pilot projectile velocity and that of the missile are equal or almost equal; the projectiles shapes and weights are selected so as the rocket velocity decreases it is equal less they that of the pilot projectile, in the range wanted.

Preferably, in the case of an antitank rocket launcher, the lines of fire of both projectiles are parallel; the tracer bullet muzzle velocity and the velocity acquired by the rocket at the end of the propelling charge combustion are practically the same. At the moment when the rocket begins its free flight, the distance between the tracer bullet and the rocket is due to less rapid acquirement of velocity by the latter.

The invention is not limited to the examples of embodiment as represented and described, but various modifications can be made therein, without departing from the scope of the invention.

What I claim is:

1. A weapon including in combination, a rocket launcher and a gun attached to said launcher with its axis parallel to that of the launcher to move with said rocket launcher, an artillery tracer projectile for firing from said gun constructed to be crushed upon impact with a target to deposit tracer material thereon which continues to burn, and a rocket provided with guidance means for following said tracer projectile through the entirety of its path to impact the position of said deposited tracer material, wherein said guidance means comprises means rotating the rocket about its axis through its trajectory and at least two guidance devices each including a pair of aerodynamic flaps externally and symmetrically arranged on the rocket about an axial plane and independently movable, a lens positioned on said rocket with its optical axis parallel to the axis of the rocket to receive radiant energy from said tracer material as the rocket is launched to follow the path of said projectile, two radiant energy detector cells each symmetrically placed upon two equal sectors of one circle located in the focal plane of said lens with planes identical to that of the corresponding said aerodynamic flaps, insulating sectors smaller than said detector cells spaced between the cells on said circle, amplifiers cou pled to the two cells, and control means responsive to the amplifiers for moving said corresponding flaps proportional to the currents generated in the respective 

1. A weapon including in combination, a rocket launcher and a gun attached to said launcher with its axis parallel to that of the launcher to move with said rocket launcher, an artillery tracer projectile for firing from said gun constructed to be crushed upon impact with a target to deposit tracer material thereon which continues to burn, and a rocket provided with guidance means for following said tracer projectile through the entirety of its path to impact the position of said deposited tracer material, wherein said guidance means comprises means rotating the rocket about its axis through its trajectory and at least two guidance devices each including a pair of aerodynamic flaps externally and symmetrically arranged on the rocket about an axial plane and independently movable, a lens positioned on said rocket with its optical axis parallel to the axis of the rocket to receive radiant energy from said tracer material as the rocket is launched to follow the path of said projectile, two radiant energy detector cells each symmetrically placed upon two equal sectors of one circle located in the focal plane of said lens with planes identical to that of the corresponding said aerodynamic flaps, insulating sectors smaller than said detector cells spaced between the cells on said circle, amplifiers coupled to the two cells, and control means responsive to the amplifiers for moving said corresponding flaps proportional to the currents generated in the respective detector cells. 